1. Field of the Invention
This invention relates to new and improved siphon heads for draining away accumulated water on a flat roof where conventional water drainage systems fail to allow roofs to drain dry. The invention further concerns a new and improved system for evacuating water from flat roofs where the flat roofs have either a smooth or a rough texture, and different types of siphon heads are provided for achieving this result.
All flat roofs have the potential to develop problems with water standing in low areas especially on older buildings. It has been found that old drain placements made at the time of the original construction of flat roof type buildings often become ineffective due to the settling of the buildings in which event the old drains are therefore no longer effective for removing the water sitting on such roofs. Water weight is heavy at 8 pounds per gallon and water accumulations on flat type roofs can cause the building to settle or sink even further to further damage the building. Water that is deep enough which does not evaporate within 48 hours tends to seep into small pin holes and perforations in the roof membrane trapping moisture underneath its surface which causes a blistering effect when exposed to sunlight and will result in breaking down the insulation and sub structure beneath the roof. All of this damage tends to create the need for an entirely new roof with pitch to cause natural drainage to occur after a rainfall or melting ice. A second flat roof may sometimes be applied if the building can support its weight which requires professional evaluation. A third roof of pitch and gravel over an original roof is never advised.
2. Description of the Prior Art
Various types of water drainage systems have been developed in the past, but none are known that can effectively drain flat roofs dry using various types of siphons for use depending on whether the flat roof has a "rough" or "smooth" roof surface. My new roof drainage systems can be moved about a flat roof of a building to siphon pools or ponds or pools of water at preselected locations to effectuate the draining. Many original roof drains are no longer effective to drain the ponds due to new low spots coming into existence on the roof out-of-effective drain range of existing drains. My invention also utilizes new and improved apparatus and techniques for priming the siphon lines.
Typical examples of prior roof draining systems can be found in a variety of issued U.S. Patents including U.S. Pat. No. Re. 28,491 issued to Robert L. Kundert. This patent discloses a roof draining system that automatically siphons water from roofs that are not completely self draining. While this patent shows a system that works automatically, it fails to disclose how ponds on flat roofs can be drained through the use of portable siphons. This patent also fails to show or teach any siphon heads that are adapted for siphoning rough textured or smooth textured roof surfaces. The Kundert roof draining apparatus operates to suction or siphon sumps that are cut into the roof top which is an expensive approach.
Another example of a drain system for use on flat roofs is shown in U.S. Pat. No. 4,513,768. The roof drain system that is disclosed in this patent does not readily lend itself to draining ponds or pools which have come into existence at a point in time after the original drains have been installed, and where new low spots have come into existence which cannot be readily drained by the drain system that was previously installed.
It has also come to my attention that there are other patents including U.S. Pat. No. 4,171,706 which specifically relate to a method for removing water from a ponding area of a flat roof having a run-off system which is no longer operable to drain water from the ponding area. This patent speaks about the problem that is known to exist in situations where flat roof constructions settle or sag producing so-called low spots which are lower than the areas where the roof is supported which lower areas produce ponding areas when a rain condition commences. These ponding areas tend to increase and have a so-called snowballing effect on the roof since the added weight of the ponding water causes additional sag. It has also been known and found that the existence of standing water on a roof generates added stresses which can cause blistering, leaking and similar problems all of which tend to shorten the life span of a roof. This patent teaches the use of a hose 40 which is "rested upon a ponding surface area of the roof" so that when a rain condition occurs the build up of water in the ponding area will cover the openings 44 (FIG. 4). This hose 40 has a plug 42 that is fixedly secured within the extremity by cement. The plug also has a series of inlet openings 44 which permit the free end portion of the hose 40 to be rested upon a ponding surface area so that when a rain condition occurs the build up of water in the ponding area will cover the openings 44. My invention has a number of features which are not disclosed in this patent, and as a result my water drainage system can be more effectively operated to ponds on drain flat roofs as previously described.